The aim of the study is to examine the effect of teaching activities supported with metaconceptual processes on 7th grade students' conceptual understandings and attitudes of law related concepts in social studies course when compared with traditional instruction. In this quasi-experimental study, convenience-sampling method was used. This study was conducted in four classes of a social studies teacher. Two of the classes were randomly assigned as experimental group and the other two classes were randomly assigned as control group. The participants composed of 114 7th grade middle school students enrolled in a state school in Ankara. Experimental group was exposed to teaching activities supported with metaconceptual processes while control group was exposed to traditional teaching based on the current teaching program. For data collection, conceptual understanding and attitudes tests developed by researcher were used. The results indicate that teaching activities facilitating metaconceptual processes had more positive impact on students' conceptual understanding and attitudes towards law related concepts. [This study was presented verbally in "The 6th Biennial Meeting of the Early Special Interest Group 16 Metacognition" organized at Bogaziçi University between 3rd and 6th of September, 2014.]